Anti-HBs titre categories (mIU/ml) Diabetics Non-diabetics MCP No. % No. % After first booster n=45   n=45   0.028* <10 7 15.6  0 0.0 10-100 2 4.4  4 8.9 >100 36 80.0 41  91.1 After second booster n= 9   n= 4   0.109! 10-100 4° 44.4  0 0.0 >100 5˜ 55.6  4 100.0 After third booster n= 4       NA >100 4 100.0  0 0.0 Z(P) -2.428 (0.015*) £ -2.00(0.046*)

Table 4: Anti-HBs titre categories of HBV immune response among the studied students after booster doses measured in mIU/ml. Z: Wilcoxon test of two related groups, MCP: P value based on Mont Carlo exact probability, ! P value based on Fisher exact probability P£: P value based on Friedman test of several related samples, 4° : Three from the 7 unprotected after the 1st boosting and one from the 2 having anti-HBs level of 10-100 mIU/ml after the 1st boosting, 5˜ : Four from the 7 unprotected after the 1st boosting and one from the 2 having anti-HBs level of 10-100 mIU/ml after the 1st boosting.